1. Field of the Invention
The present invention is generally concerned with control buttons which must be pressed to operate an underlying component, for example an electrical component.
2. Description of the Prior Art
Usually called "punch buttons" when their shape is such that they can be operated with the palm of the hand, these control buttons usually include a guide body by means of which they can be mounted on a support of any kind, a piston mobile in the guide body against return spring means to operate the underlying component, and a generally mushroom-shaped control member mobile axially relative to the guide body between an "out" inoperative position and an "in" operative position and including a head which is actuated by the user and a spindle acting on the piston and, through the intermediary of the latter, on the underlying component.
The present invention is more particularly concerned with control buttons usually called "push-and-turn latching" control buttons which further include a retaining ring which is fixed relative to the guide body in the axial direction and prevented from rotating relative to the guide body, extends around the spindle of the control member and has, subordinate to the retaining ring, hooking means adapted to hold the control member releasably in the in position when action has been applied to the latter accordingly and cam means adapted to return said control member to its initial angular position when it is released after having been turned in the depressed position to disengage the hooking means.
Control buttons of this kind are used to disconnect equipment semi-permanently, for example.
In some applications at least it would seem desirable for the "in" or "out" position of the control member to be clearly indicated, the travel of the control member between its two positions being usually too small for its position to be determined unambiguously merely by looking at it.
In a first aspect, a general object of the present invention is an arrangement which meets this requirement in a particularly simple and effective manner.